Up until 2010, Sub-Lt. Jeffrey Delisle worked for both the Chief of Defence Intelligence and at the Strategic Joint Staff, which oversees virtually every major aspect of the military's domestic and international plans and operations. (AP) | AP

OTTAWA - The junior naval officer accused of spying for a foreign entity spent almost his entire career in intelligence and, at one time, worked in the military's nerve-centre at National Defence Headquarters, defence officials quietly acknowledged on Wednesday.

Up until 2010, Sub-Lt. Jeffrey Delisle worked for both the Chief of Defence Intelligence and at the Strategic Joint Staff, which oversees virtually every major aspect of the military's domestic and international plans and operations.

The revelation opens the possibility that the 40-year-old had access to even more highly-classified data than what was potentially available at his current posting in Trinity, a highly-secure naval intelligence centre in Halifax.

The military, in a written response to questions by The Canadian Press, said that Delisle joined the military as a reservist private in 1996 and was posted to the 3 Intelligence Company in the Nova Scotia capital.

He went on to join the regular forces in 2001, was promoted to sergeant before being accepted at university for two years in Kingston, Ont. as an officer candidate and eventually landed back in Halifax at the army's Atlantic headquarters.

Delisle was posted to Trinity in August of last year.

Court papers filed along with the charges against him allege that he began giving up secrets as far back as 2007.

Putting an accused navy spy on trial represents a potential legal and intelligence nightmare for the Harper government, one where it will have to resist the temptation to dispense justice in secret, say experts.

If the case against Delisle goes to trial, the Crown will have a significant arsenal of tools to bar the door to the public and media, but at the same time there will be pressure on prosecutors to hold as much of the proceedings as possible in open court.

The intelligence officer was charged Monday with passing secrets to a "foreign entity" under Canada’s Security of Information Act, in a first of its kind case.

Even with the new information about his career, many questions remain about Delisle, who moved to the East Coast from Ontario.

It was revealed Wednesday that he declared bankruptcy 12 years ago, before he joined the military full-time. The 1998 bankruptcy filing showed Delisle owed $18,587 to creditors but had assets of just $1,000.

Espionage trials are rare because there's a danger the accused will spill even more secrets during the court proceedings — a defence tactic known as "greymail," said Craig Forcese, a law professor at the University of Ottawa who has written extensively on national security.

"There's always a risk."

The warning came as the country's top military commander moved to buff away some of the tarnish the controversy has left on the Forces.

Chief of Defence Staff Gen. Walt Natynczyk, in his first public comment on the case, said the military takes the security of sensitive information seriously and is always mindful of the effects of unauthorized disclosure.

In a written statement, the chief of defence staff said everyone handling secrets is required to not only observe stringent procedures, but is expected to conduct themselves ethically, and in a manner consistent with military values.

Natynczyk joined Prime Minister Stephen Harper and Defence Minister Peter MacKay in refusing to address questions about the case — a silence that experts say only lends more urgency to airing the matter in public.

The Charter of Rights enshrines the principle of open court hearings and it's "quite unusual" for a criminal proceeding to be behind closed doors, Forcese said.

Still, the Criminal Code allows a judge to exclude members of the public, including the media, for all or part of the proceedings if the judge believes it is necessary to protect international relations or national security.

"That could be an issue, and you may end up with a closed portion of the proceeding," said Forcese.

However, Delisle and his lawyer would be able to attend the hearing.

The case will be "not only a test of the viability of the evidence but to what extent it's made public if it's secret," said lawyer Ron Atkey, a former chairman of the watchdog that keeps an eye on the Canadian Security Intelligence Service.

"You may not see some things," he said.

"In trials like this in the U.S., a lot of the evidence has been in camera."

Experts say the government could try to shield sensitive information from Delisle and the public by invoking a section of the Canada Evidence Act that allows it to cloak material whose release would endanger national security.

Section 38 of that legislation was used extensively to keep documents pertaining to the treatment of Afghan prisoners away from a military watchdog that was holding a public hearing.

The prolonged battle over disclosure set off a political crisis in late 2009 that culminated with a Liberal threat to topple the minority Conservative government. Harper avoided the confrontation by asking the Governor General to dissolve Parliament.

Forcese said the government could try to keep some information secret, but it would not then be able to turn around and use that material for its own purposes.

"So it runs the risk of removing from play information that it needs to secure the conviction."

Former CSIS director Reid Morden said there's no need for a closed-door trial.

"I'm in favour of people being as open as possible," he said. "I think you can make distinctions between what really cuts to the core of national security, including allied security, and a lot of froth around the edges."

Another question is whether a case would be heard by a jury or judge alone. A jury trial could be "quite awkward" given that confidential information will be circulating in the court room, Forcese said.

"You can't really security clear your jury. So how it plays out in terms of whether the accused is going to opt for a jury or not presents some interesting questions."

-By Jim Bronskill and Murray Brewster of The Canadian Press, with files from Alison Auld in Halifax.